Answer: The function f is nonnegative between x=-3 and x=3
Given:
The given integral is also equal to the area between the curve of f(x)=9-x². To find the x-values that will maximize the value of the given, we could equate 9-x² to 0 and solve for x:
Checking the graph:
With these, we can say that the function f is nonnegative between x=-3 and x=3